CVE-2026-20054: Cisco Cyber Vision

Medium severity, CVSS 5.8. EPSS: 0.4% chance of exploitation in the next 30 days.

Multiple Cisco products are affected by a vulnerability in the Snort 3 VBA feature that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash.  This vulnerability is due to improper error checking when decompressing VBA data. An attacker could exploit this vulnerability by sending crafted VBA data to the Snort 3 Detection Engine on the targeted device. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to enter an infinite loop, causing a DoS condition.

Affected products

• Cisco Cyber Vision: version 3.0.0 only; version 3.0.1 only; version 3.0.2 only; version 3.0.3 only; version 3.0.4 only; version 3.0.5 only; …
• Cisco Secure Firewall Threat Defense: version 7.2.0 only; version 7.2.0.1 only; version 7.2.1 only; version 7.2.2 only; version 7.2.3 only; version 7.2.4 only; …
• Cisco Snort: from 3.0.0-233, before 3.9.3.0 (fixed in 3.9.3.0)
• Cisco Unified Threat Defense Snort Intrusion Prevention System Engine: version 3.17.0s only; version 3.17.1s only; version 16.6.1 only; version 16.6.5 only; version 16.6.6 only; version 16.6.7a only; …

Published 2026-03-04. Last modified 2026-08-20.